Polymers that have been used to form medical device components include various amide polymers such as polyamides, polyether-block-amides and (meth)acrylamide polymers and copolymers. Amide polymers are typically substantially radiolucent, that is they have little or no opacity to X-rays and other high energy radiation sources. In medical device applications it would be desirable if these materials can be rendered more radiopaque, so that they can be more easily monitored in the body, for instance to track the movement of a catheter through the body or the inflation of a balloon at a site, or the like.